1. You can select multiple checkboxs (square one), But you only select one from radio buttons. (circle one)2. Why you need a menu or check box to be able to drag and drop? Do you really mean that you want to be able to drag and drop those vectors. You just create ArrorSet in the view and it can be dragged one at a time.

You can also create ArrowSet which is invisible. And when you click on it, make one of the arrow move with the mouse position (You can get mouse coordinate x,y from property of DrawingPanel). Then you have a drag and drop effect.

I believe I can give you better suggestion if you write download in detail what you really want to do.

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There is some error when I open your xml. However, I create another example for you.I think the effect shown in the following applet is what you want. You can download the xml file and find out what I did. You can also drag the vector.

Because you are asking java to do the same instruction: VIEW2=showComponent; n-1 times.

for loop is used for doing repeated jobs. Normally works better with array.i=1; // is for initialization (Normally, i will be set to 0, because array starts from 0, for example: if you define x[n], then you will have n variables: x[0], x[1],...[x[n-1])

Then it will do whatever inside the for loop, when it is done, it will execute i++ (i++; is the same as i=i+1;). So , i become 2, and it will do whatever inside the for loop again,... repeate if i<n is satisfied.